Twin-nibbed marking pen



FIG. 1 is a perspective view of a twin-nibbed marking pen showing my new design;

FIG. 2 is a rear elevational view;

FIG. 3 is a front elevational view;

FIG. 4 is a right side elevational view, the left side being a mirror image thereof;

FIG. 5 is a top plan view;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view of my design with the cap members removed for convenience of illustration;

FIG. 8 is a front elevational view of FIG. 7;

FIG. 9 is a top plan view of FIG. 7; and

FIG. 10 is a bottom plan view of FIG. 7. 

The ornamental design for a twin-nibbed marking pen, as shown and described. 